Automobile heater



Oct. 28, 1941. H. J. DE N. M-ccoLLuM 2,260,535

AUTOMOBILE HEATER Filed April 6, 1938 Patented Oct. l2 8, 1941 vUNITEDSTATES PA'VI'ENMTl OFFICE 2,260,535 AUTOMQBIL HEATER Henry J. De N.McCollum, Evanston, Ill.

Application April 6, 1938, Serial No. 200,316

3 Claims.

My invention relates generally to automobile heaters, and moreparticularly to automobile and similar heaters of the internalcombustion type.

An automobile heater of the general type to which my present inventionpertains is disclosed and claimed in my copending application, SerialNo. 61,213, filed January 28, 1936, now Patent 2,191,178, February 20,1940.

My present invention relates'to various modications and improvements incombustion chambers utilizable in heaters of this type.

It is therefore an object of my invention to provide an improvedcombustion chamber for internal combustion heaters for automobiles andthe like.

A further object is to provide an improved combustion chamber and meansfor supplying fuel to the combustion chamber usable in a heater of theinternal combustion type.

Other objects will appear from the following description, referencebeing had to the accompanying drawing, which is a fragmentary centralvertical sectional view of an automobile heater incorporating animproved form of combustion chamber and fuel admitting means.

The improved combustion chamber of my invention may be incorporated in aheater of the general type shown in the drawing, which comprises a frameplate I which is mounted upon the dash I2 of a vehicle by means ofbrackets I4,

l a heat radiating plate I6, and cap screws I8. A

combustion chamber casting 20 is secured t0 the plate I0, and isprovided with a tubular outlet projection 22 which is connected by meansof a suitable conduit 24 with the intake manifold 26 of the automobileengine or with any other suitable source of suction. The rate of flow ofgases of combustion to the intake manifold is determined by a flowrestricting nozzle 28 having a Venturi-shaped passageway extendingtherethrough, the mouth of the nozzle 28 forming a seat for a valve 30at the end of a valve stem 32.

The valve stem 32 is manually operated by means of a handle button 34secured at the end opposite the valve 30. The valve 30 is locatedadjacent the outlet end of a circuitous passageway 36 formed in aradiator casting 38. The latter casting is surrounded by a copper shell40 over which flanged heat radiating fins 42 are pressed.

An apertured baille plate 44 covers the ends of thesections of thepassageway 36. Air from the passenger compartment of the vehicle isforced 'downwardly past the fins 42 by means of a fan 46 operated by anelectric motor 48. The motor,

fan, and radiator are enclosed in a suitable housing 50.

The casting 20 contains a combustion chamber 52 generally cylindrical inshape, the outlet end of which isformed by a re-igniter plug 54 which ismade of a suitable refractory ceramic material. A baffle plate 56 issecured in the other end of the combustion chamber 52 by being pressedthereinto, this baffle plate having recesses along its peripheral edgeto permit the flow of air into the combustion chamber. .An igniterchamber 58 is located at the side of the combustion chamber 52 andcommunicates therewith through an aperture 60. Within this igniterchamber 58 may be any suitable ignition means such as an electricallyheated coil of nickelchromium wire, a spark plug, or similar device.

A carbureting device 62 is threaded in the top of the combustion chambercasting 20, and communicateswith the chamber therein through inlet port64. The carbureting device 621 may be of any simple conventionalconstruction, and is herein disclosed as having a Venturi-shaped pas-Isageway 66 to which air is supplied from th atmosphere through ports 68and gasoline or other liquid fuel supplied through'a jet 10,' the nozzleof which terminates adjacent the throat of the passageway 66. Fuel issupplied to the jet 10 through a conduit I2 which is connected toA asuitable container 'I4 of liquid fuel, which in most instances will bethe float-bowl of the engine carburetor but may be a suitable auxiliaryreservoir for gasoline or other fuel.

Y A suitable device 'I6 for insuring an` adequate supply of Ifuel duringthe-starting period is preferably provided so as to facilitate theignition of the fuel mixture in the combustion chamber by enriching thismixture during the initial period of operation. This device is morefully disclosed and is claimed in my copending application, Serial No.177,077, filed November 29, 1937, now Patent 2,192,688, March 5, 1940.

The carbureting device 62 supplies a mixture of fuel and air which isunnecessarily rich and I have therefore provided an auxiliary air inletfor supplying air at the rate required to effect most eflcientcombustion. This means comprises a tube 18 which is pressed into thecasting 20 and is filled. with steel wool or similar heat con- 5.', a,similar plug-having a port of different size,

turi-shaped passageway 66 of the latter being effective to createsuction in the jet 19 andthereby raise the liquid fuel from the fuelsupplyl reservoir 14. r

By suitable means, not herein disclosed, the electrical ignitercontained within the chamber 58 is electrically heated during suchperiod as is necessary to assure ignition of the fuel mixture beingsupplied to the. combustion chamber. The mixture in the combustionchamber will thus be ignited and the products of combustion will flowthrough the passageways in the re-igniter plug 54, through thecircuitous passageway 3'6 in the radiator casting 38, and hence past theopen valve 30 through the conduit 24 into the intake manifold 26.

As previously stated, the device 16 is effective to supply fuel at anincreased rate for a short period after `the operation of the heater hasbeen initiated and at a lesser rate thereafter.

To increase the combustion eillciency of the device, it is desirable toadmit additionalair to the combustion chamber, and this is accomplishedby means of the tube 'I8 which is in heat conducting relationship withthecasting 20 and thus will, after the heater has been in operation ashort time, be heated to a relatively high temperature. The air which isdrawn in through the inlet port 84 in theA metering plug 82 is thuspre-heated upon passing through the steel wool filed tube 1B, andimpinges upon the baille plate 56 which, being exposed tothe direct heato'f the llame in the combustion chamber, is at a relatively hightemperature. The auxiliary air is thus heated to a high temperaturebefore it passes into the combustion chamber through the recesses formedaround the periphery of the baille plate 56. 'I'his auxiliary air isthus fed into the combustion chamber in a relatively thinstreamfsubstantially circular in crosssection due to the shape of the4recesses in the baille plate, and as aresult is very effectivelydistributed for assuring complete combustion of the charge beingsupplied through the inlet port 54.

After a short period of operation the re-igniter plug 54 will becomeheated to a suiliciently high temperature to assure re-ignition of thecombustible mixture'being fed to the combustion chamber, should theflame become extinguished vaccidentally due to a temporary drop in theincontrol the supply of current to the motor 48 and thereby causeoperation of the fan and circulation of the air in the passengercompartment indicated in the figure, wherein the ange of' the plug 82serves as a means to secure a bimetallic thermostatic element 85in'place, the element 85 having a. portion 86 which forms a valveclosing the end of the port 84 when itis at atmospheric temperatures,but which is adapted to be raised therefrom due to change in the shapeof the thermostatic element when it attains the temperature of normaloperation of the heater. Suitable vibration damping means may be addedto thermostatic valve 85 to check liuttering thereof.

While I have shown and described a particular embodimentof myinvention,. it will be apparent to those skilled in the art that theinvention may be utilized in other forms of construction. I thereforedesire by the following claims to include within the scope of myinvention not only the constructions herein disclosed,

but also such other embodiments of the invenlationship with said bodyand a plug having a metering orifice for regulating the rate at whichauxiliary air mayiiow into said tube and therethrough to said combustionchamber. 2. In an automobile heater of the internal com f bustionl type,the combination of a body of heat conducting material having acombustion chamber formed therein, means to supply a combustible mixtureof fuel and air to said chamber.

' ber, said last-named means comprising a tubulary take manifold vacuum,as may occur upon sud-l filed January 14, 1937, now Patent 2,191,174,y

February 20, 1940, as well as in my aforesaid application, Serial No.61,213; As disclosed in these applications. the thermostatic means mayalso and means to supply auxiliary air to said chamelement in heatconducting relationship with said body for preheating the auxiliary airsupply, and temperature responsive means for controlling the admissionof the auxiliary air supply to said tubular element.

3. In an automobile heater of the internal combustion type, thecombination of a .body of heat conducting material having a combustionchamber formed therein, means to supply a combustible mixture of fueland air to said chamber, and means to supply preheated auxiliary air tosaid chamber, said last-mentioned means comprising a relatively longtubular extension formed integrally with said body, a tube mountedwithin said extension and communicating with the comv' ductingrelationship to said tubular extension for controlling the admission ofauxiliary air.

HENRY JTDE N. MCCOLLUM.

